Precision immunotherapy for head and neck cancer: therapeutic combinations, biomarker strategies, and translational challenges.

This review article examines how to move beyond single-agent immune checkpoint inhibition in head and neck squamous cell carcinoma (HNSCC) toward rational, biomarker‑driven combination strategies.

Key points:

• Current limitation of ICIs in HNSCC

• ICIs have changed the treatment landscape but yield durable benefit in only a subset of biologically selected patients.
• Empiric monotherapy is insufficient; there is a need for precision‑guided combinations that actively overcome immune resistance.

• Focus on combination strategies

• Discusses combinations of ICIs with:

• Radiotherapy (RT): leveraging immunogenic cell death, enhanced antigen release, and improved antigen presentation.
• Chemotherapy: cytoreduction plus potential immune modulation.
• Emerging non‑cytotoxic sensitizers: including innate immune pathway activators, metabolic modulators, microbiome-directed approaches, and advanced drug delivery systems.

• Particular emphasis is placed on neoadjuvant and perioperative use, where reshaping the tumor immune microenvironment may improve long-term disease control.

• Tumor immune microenvironment (TIME) remodeling

• The goal is not simply boosting immune activation but reprogramming an immunologically “cold” TIME into an “interrogable” one, by:

• Restoring antigen presentation.
• Improving spatial organization of immune cells.
• Enhancing effector T‑cell function and persistence.

• Evolving biomarkers and patient selection

• Highlights a more integrated biomarker framework that goes beyond PD‑L1 alone to include:

• Tumor mutational burden.
• Tertiary lymphoid structures.
• Tissue‑resident memory T cells.
• Spatial immune architecture.

• These markers are framed as tools for stratifying patients, sequencing therapies, and optimizing combination regimens.

• Barriers to clinical translation

• Inadequate incorporation of biomarkers into trial design.
• Heterogeneous and sometimes suboptimal clinical trial structures.
• Mismatch between biological/immunologic endpoints and hard survival outcomes.

• Overall conclusion

• The field is moving from empiric combination therapy toward immune‑centric precision immuno‑oncology in HNSCC.
• The authors argue for biomarker‑driven trial designs, longitudinal immune monitoring, and close multidisciplinary collaboration to convert mechanistic synergy into durable clinical benefit.